diff options
| author | Andy Lutomirski <[email protected]> | 2016-04-02 07:01:40 -0700 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2016-04-13 11:37:46 +0200 |
| commit | b828b79fcced0e66492590707649dbfaea6435e6 (patch) | |
| tree | b7e03be5be31ee11357f156890c04975118524de | |
| parent | 4985ce15a397e9b6541548efe3b9ffac2dda9127 (diff) | |
x86/msr: Set the return value to zero when native_rdmsr_safe() fails
This will cause unchecked native_rdmsr_safe() failures to return
deterministic results.
Tested-by: Boris Ostrovsky <[email protected]>
Signed-off-by: Andy Lutomirski <[email protected]>
Acked-by: Linus Torvalds <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Arjan van de Ven <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: KVM list <[email protected]>
Cc: Paolo Bonzini <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: xen-devel <[email protected]>
Link: http://lkml.kernel.org/r/515fb611449a755312a476cfe11675906e7ddf6c.1459605520.git.luto@kernel.org
Signed-off-by: Ingo Molnar <[email protected]>
| -rw-r--r-- | arch/x86/include/asm/msr.h | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/arch/x86/include/asm/msr.h b/arch/x86/include/asm/msr.h index 00050c034a13..7dc1d8fef7fd 100644 --- a/arch/x86/include/asm/msr.h +++ b/arch/x86/include/asm/msr.h @@ -101,7 +101,10 @@ static inline unsigned long long native_read_msr_safe(unsigned int msr, asm volatile("2: rdmsr ; xor %[err],%[err]\n" "1:\n\t" ".section .fixup,\"ax\"\n\t" - "3: mov %[fault],%[err] ; jmp 1b\n\t" + "3: mov %[fault],%[err]\n\t" + "xorl %%eax, %%eax\n\t" + "xorl %%edx, %%edx\n\t" + "jmp 1b\n\t" ".previous\n\t" _ASM_EXTABLE(2b, 3b) : [err] "=r" (*err), EAX_EDX_RET(val, low, high) |